1. Field of the Invention
The present invention is directed to a thin-film solar module of the type having an electrically conductive substrate, as well as to a method for manufacturing such a module.
2. Description of the Prior Art
Thin-film solar cells can be produced directly on large-area substrates. The use of economically priced substrates such as, for example, window glass, production in plasma deposition systems having high area throughput, wirings integrated into the manufacturing process, and the relatively low costs of materials of the thin semiconductor layer are important advantages of thin-film solar modules compared to solar modules with crystalline solar cells.
The most significant disadvantage of thin-film solar modules and, in particular, those composed of amorphous silicon, is in the relatively low efficiency. For offering the same electrical power, this requires a larger module area compared to crystalline solar cells and requires a correspondingly larger base area for supporting the modules.
It has therefore already been proposed that facade elements composed of glass be coated, in particular, with thin-film solar cells, or that solar modules on glass substrates be employed as facade elements. In addition to the photovoltaically generated current, the solar modules can serve both for decoratively fashioning the facade and to provide a separate technical function. For example, semi-transparent solar modules can serve as windows, whereas solar modules equipped with appropriate insulating glass can serve the purpose of thermal insulation of buildings. Embodiments of solar modules utilized in this way are disclosed, for example, in U.S. Pat. No. 5,128,181.
In this context, it is a disadvantage that, using thin-film solar modules, one is largely bound to the employment of flat glass panes as the substrate material. This highly restricts the possibility of functional use thereof as a facade element.